Searching for Solitons in Heavy-Ion Reactions near the Fermi Energy

Abstract

Solitons are special shape-conserving hydrodynamical solutions that appear in many areas of physics. Here, we explore the existence of such solutions in microscopic descriptions of the heavy ion reaction $^{12}$C + $^{28}$Si $\rightarrow$ $^{12}$C$^*$ + 7$\alpha$ in the range E/A=10-65 MeV/u. After recognizing the centrality of the collision and time-reversibility as fundamental requirements for the presence of solitonic $^{12}$C, we utilize the Hybrid $\alpha$-Cluster model for our analysis with a novel methodology. Our results suggest soliton production for E/A=25-45 MeV/u in the forward direction, with a total cross section being at least in the order of a few $\mu$b. This, apart from being encouraging for possible experimental studies, maybe connected to possible toroid states of $^{28}$Si at low angular momenta.